In a power supply system applied to an electric powered vehicle, a power conversion apparatus that converts output electric power of a power storage device mounted on the vehicle into electric power for driving a drive motor is configured with a combination of a converter that can step-up the output voltage of the power storage device, and an inverter that converts output DC voltage of the converter into AC voltage and applies the AC voltage to the inverter.
Japanese Patent Laying-Open No. 2009-159663 (PTD 1) discloses a power supply system that includes a plurality of power storage devices, and a plurality of converters provided between DC power lines connected to inverters and the plurality of power storage devices, respectively. In the power supply system described in PTD 1, one of two converters is controlled in accordance with voltage control for bringing a voltage value of a DC power line to a prescribed voltage target value, while the other converter is controlled in accordance with current control for bringing the charge and discharge current of a corresponding power storage device to a prescribed current target value.